Manufacture of steel



Patented Nov. Ml, 11922.

UNHTED STATES ROBERT ABBOTT HADFIELD,

or WESTMINSTER, ENGLAND.

MANUFACTURE OF STEEL.

Iifo Drawing.

To all whom it may concern:

Be it known that I, Sir Ronnn'r Anno'r'r HADFIELD, F. R. S., a subjectof the King of Great Britain and Ireland, residing at Westminster,England, have invented new or Improved Manufacture of Steel, of Whichthe following is a specification.

This invention has for object the manufacture of a manganese steel oriron alloy possessing amongst other qualities, great toughness andresistance to perforation, particularly when in the form of heat treatedsheets or plates.

I have found that this object can be attained by adding copper to analloy of iron high in manganese and relatively low in carbon. The alloyof iron, manganese and carbon may vary in the percentage composition ofits constituents. It may for earample be of the kind or character oford1- nary manganese steel, that is to say, comprising iron with about10 to 15% or it may be up to 17% of manganese and from about .9 to 1.5%of carbon, but the invention is not limited to these percentages, themain feature of the new steel or alloy being the presence therein ofcopper. The copper may be added to the manganese steel when in themolten state, or to the mixture of iron and ferro-manganese, or iron andmanganese, used to produce the manganese steel, and meltedsimultaneously therewith 'the resulting new steel being cast into ingotsor other castings. The copper may be added as such or in any othersuitable form. The amount of copper to be added to form the new steel oralloy may vary but usually it will be within the limits of about one percent to about three or four per cent.

The quality of the new manganese steel or iron alloy can be improved, atleast for some purposes, by subjecting it to a toughening processconsisting in heating it to a high temperature, say for example fromabout 900 up to it may be 1050 C. or above but below its melting point,and cooling it quickly as by quenching it in water. The "new steel whenthus heat treated and water quenched, usually called water toughened.has a greater toughness and resistance to perforation than ordinarymanganese steel of commerce.

For many purposes, the new steel or alloy may advantageously be rolledinto the form of sheets or plates (hereinafter referred to as sheets) orof rods, bars or wire, and he Application filed July 13,

1916. Serial No. 108,995.

subjected to the toughening process referred to, when in such form, orpreviouslv as when in the form of ingots or slabs. If. desired, thetoughenin process may be repeated. Thenew steel or alloy can also beused for castings of any desired shape and be heat treated or not as maybe required.

The amount of silicon present in the new steel or alloy may vary from asmall percentage say up 'to about 2% or it may be above. Also, anotherelement such for example as chromium, nickel, cobalt, vanadium,tungsten, titanium or aluminium. or two or more of such elements, may beadded to thesteel or alloy for the purpose of improving or varying thequality thereof. '1 he percentage of such element or elements employedis such say for example from one half of one per cent to seven per cent.as to give to the resulting steel or iron allov the varying desiredqualities.

By way of example, it may be stated that good results have been obtainedwith a manganesesteel or iron alloy according to the invention and inthe form of water toughened plates or sheets, when containing about 95%of carbon, about 1.25% of sili con, about 1.44% of copper and about12.72% of manganeseand also with a manganese steel or iron alloycontaining about 1.24% of carbon, about .1170 silicon. about 1.18% ofcopper and about 12.42% of manganese.

The new steel or iron alloy can be used for various purposes and ineither the rolled. forged or cast condition.

What I claim is:-

1. Manganese steel with from about one per cent to four per cent ofcopper.

2. Steel having great toughness and resistance to perforation andcontaining iron with from about ten to seventeen per cent of manganese,about nine tenths per cent to two per cent of carbon, and from about oneper cent to four per cent of copper.

3. A steel alloy containing iron and carbon with from about ten per centand upwards of manganese and with from about one to four per cent ofcopper and treated by heat to above about 900 C. and below its meltingpoint and then cooled quickly.

4. Manganese steel retaining from about one to four per cent of copperand treated by heat to from about 900 C. and below its melting point andthen cooled quickly.

5. As a new article of manufacture, steel having great hardness andtoughness and containing at least ten per cent of manganese and up toabout four per cent of copper.

6. As a new article of manufacture, manganese steelin wrought form andcontaining up to about four per cent of copper and treated by heat tofrom about 900 (land below its melting point and then cooled quickly.

7. As a new article of manufacture, manganese steel in sheet formalloyed with from about one to four per cent of copper and treated byheat above 900 C. and below its melting point and then cooled quickly.

8. An alloy of iron high in manganese, low in carbon and containing asubstantial amount of copper.

9. A steel alloy containing iron and car-- I bon with from about ten percent and upwards of manganese andfrom' about one per cent to four percent of copper.

10. A. steel alloy containing carbon up to one decimal five per cent,manganese from about ten per cent to about seventeen per cent and copperfrom about one per cent to four per cent.

11. As a new article of manufacture, a steel alloy having greattoughness and resistance to perforation and containing iron and carbonwith from about ten per cent to seventeen per cent of manganese and fromabout one per cent to about four per cent of copper.

12. As a new article of manufacture, manganese steel having greattoughness and re sistance to penetration and wrought form and containingfrom about one per cent to four per cent of copper.

13. As a new article of manufacture, manganese steel having eattoughness and reslstance to perforatlon and in sheet form and containingfrom about seven tenths to vtwo per cent of carbon, from about ten percontaining about one per cent of carbon,

about one per cent to a out two per cent of copper and about twelve percent to thirteen per cent 'of manganese. a

15. An alloy having the essential ingre dients of commercial manganesesteel together with copper, the percentage of copper being less than thepercentage of manganese.

16. An alloy composed of steel with 10 to 14% of manganese, andcopper inappreciable amount but less than 2%.

17. Manganese steel containing copper in a proportion of between 0.55%and 2%.

Signed at 22 Carlton House Terrace, Westminster, England, this sixteenthday of June 1916.

ROBERT ABBOTT HADF'IELD. Witnesses:

,WILLIAM CRoss, JOHN HAROLD HALLATT.

